Sheldon: Do you know anything about surviving psychological torture?
Tam: Because my family escaped communist Vietnam, we have to know about torture?
Sheldon: That was my thought.

Missy: What's it like to not believe in God?
Sheldon: It's great. Big fan.
Missy: Are you ever afraid you're wrong?
Sheldon: About religion? Never. About other things? Also never.

Principal Petersen: Our next young speaker needs no introduction, but that didn't stop him from writing one and making me read it. [laughter] "Fun fact." [audience groans, murmurs] I hear you. "The word 'valedictorian' is from the Latin 'valedicere,' meaning 'to say farewell.' It is primarily used in the United States, Canada, the Philippines and Armenia." Maybe that fact's more fun in Armenia. Please welcome your valedictorian, Sheldon Cooper.
Mary: Yay, Shelly!
Sheldon: Hello. I'm not very comfortable speaking in front of crowds. But there's a technique to reduce stage fright by focusing on one person in the audience and delivering your speech just to them. That's what I'll be doing today. If it weren't for this person, I wouldn't be here right now. They've taught me a lot, and it's by their example that I found the courage to move forward into this new and exciting chapter of my life. Missy... ...this is for you. Change can be scary, but I know we're going to be fine... ...because like you said, "It's okay to be scared. We just have to do it anyway." So if any of my fellow graduates are nervous about the future, know that you're not alone. I suggest you all try to be as brave as my twin sister. That's my plan. Missy, I wish I could give you advice about middle school, but I was so smart, I skipped it. If you make it to high school, we'll talk. Thank you. [applause]

Mary: Let's say grace.
Sheldon: Hang on, safety first. [puts mittens on]
George Jr.: When are you gonna get over that?
Sheldon: I would think recent events would make you value protection.
Mary: Enough.

Adult Sheldon: Ignoring things that irritate me isn't my strong suit. Obsessively fixating on them, now that's what gets me out of bed in the morning.

Adult Sheldon: My father's wisdom touched me deeply. Which is why, to this day, no matter what I'm going through, I am never irritating or abusive to any of my friends or loved ones. Ask them. They'll tell you.

Billy Sparks: Hey, Sheldon.
Sheldon: Hello, Billy.
Billy Sparks: Are you our new paperboy?
Sheldon: Yes, I'm joining the work-a-day world.
Billy Sparks: I work, too! I take care of our chickens.
Sheldon: Don't get the wrong idea. When I grow up, I plan on being a theoretical physicist.
Billy Sparks: Cool. I'm sticking with chickens.
Sheldon: All righty then. Have a nice day.
Billy Sparks: You, too. [looking at the newspaper] Oh, cool, it's Monday.